Research conclusions: The following conclusions can be obtained from the study on subgrade subsidence deformation and the prediction of the subgrade subsidence of Wuhan—Guangzhou Passenger Dedicated Line with the curve fitting method：The total subsidence in the subgrade center is bigger than that in the right and left subgrade shoulders and the total subsidence curve in the subgrade center is basically consistent with the grade rate of curve of right and left subgrade shoulders．The biggest subsidence is not in the subgrade center，but in the place 1—2 m away from the subgrade center．The predicted results with double curve fitting method and exponential curve fitting method are over big and the predicted result with three—point method iS over small．However．the predicted result with Asaoka method is mediated with no especial requirement of prediction time and hiigh accuracy．The subsidence can be controlled well by adopting CFG pile composite foundation．